condition mean min max ZT0-3 319.864545 319.864545 319.864545 ZT4-7 288.6735875 288.6735875 288.6735875 ZT8-11 314.120238 314.120238 314.120238 ZT12-15 344.762118 344.762118 344.762118 ZT16-19 411.28128449999997 411.28128449999997 411.28128449999997 ZT20-23 471.27904149999995 471.27904149999995 471.27904149999995